Spark-plug.



No. 881,684. PATENTBD MR. l0, 1908.

W. B. HAYDEN. SPARK PLUG.

APPLICATION FILED .TUNE 7. 1907..

Waksses t Zia/n a; dai/afa ,zajad. z /W l l l y e7 UNITED sTATEs WILLIAM B. HAYDEN, on NEW YoRK, N. Y.

SPARK-PLUG.

Specification of Letters Patent.

Patented March 10, 1908.

' Application sied runen, 19e?. semi No. 371,795.

State of New York, have invented new and useful Im )rovements in Spark Plugs, of which the following is a specification.

This invention relates` to three-terminal sjark plugs for use in connection with exp osive engines and one ofthe obects thereof is to provide the plug with a shie din a manner as hereinafter set forth to prevent shortcircuiting and to further so arrange the shield as to enable the removing of the lug without dismounting of the shield an to `further allow of the connecting and disconnecting of the circuit wire connection to the plug without necessitating the removal of the shield.

A further object of the invention is to provide the plug with an electrode rod in a manner as hereinafter set forth so that the said rod can be conveniently positioned and furthermore carryingmeans whereby it will be fixedly retained in position. f

A further object of the invention is to provide a three-terminal plug with means for securing compression and also with means independent of the water jacket of the cylinder of the engine for cooling the plug.

The invention further aims to rovide a three-terminal spark plug for exp osive en# gines which sha be sim le in its construction, strong, durable, e cient in its use, readily set u and comparatively inexpensive to manu acture.

With the foregoing and other objects in View, the invention consists in the novel contion thereof with the shield removed.

is an end view looking towards the inner end struction, combination and arrangement of parts hereinafter more specifically described and illustratedin the accompan ing drawings wherein is shown the' preferre embodiment of the invention, but'it is understood that changes, variations and modifications can be resorted to which come within the scope of the claims hereunto appended.`

In describing theinvention in detail, reference is had to the accompanying drawings, wherein 'like reference characters denote corresponding parts throughout the several views, and in which Figure 1 is a longitudinal sectional view of a three-terminal spark plug in accordance with this invention. Fig. 2 is a side eleva- Fig. 3

of the plug, and Fig. 4 is a detail electrode rod.

Referring to the drawings by reference characters, 1 denotes the inner section of the plug which is formed with a peripheral shoulder 2, rovided with exterior threads as at 3, 4 and urther having a hollow annular off-set 5 which constitutes a chamber 6 for receiving a cooling medium. The ofi-set 5 is formed with an inlet 7 which communicates with a cooling medium supply pi )e 8' and said odset 5 is furthermore provi ed with an outlet 9 which communicates with a discharge pipe 10. The inner end of the section 1 is provided with a pair of fixed electrodes 10a, 11, which project towards each other, but are suitably spaced apart. The section 1 of the plug is adapted to be secured to the cylinder 12 of the engine, with the inner end of said section extending into the combustion chamber of the engine. Mounted upon thescrewthreaded portion 3 of the section 1 is a comip'lession nut 13 which when screwed home edly secures compression. The plug further comprises an outer section 14 which is interiorly screw-threaded and is adapted to 4 of the section 1. The outer section 14 at its outer end is provided with an inwardl extending annular flange 15, against whic i is seated a acking 16.

Arrange `within the sections 1,'14 and projectin from the section 14 is a cylindrical bo y of insulating material 17 formed with a bore which extends entirely therethrough and the said bore is formed of two different diameters, the larger of which is arranged at the inner end of the body 17 and is indicated by the reference character 18. That ortion of the bore of smaller diameter is indicated b the reference character 19. The insulated ody 17 is formed with an annular shoulderl 20 which abuts against the packing 16 and also abuts against the acklng 21 which is interposed between the s oulner 2 0 and the outer end of the section 1. The section 14 when screwed home is adapted to secure the body 17 in position.

Extending through the bore of the cylindrical bod 17 is an electrode rod 22, which is of such ength as to project from the outer end of the body 17 and also to' extend between and past the electrodes 10, 11. The electrode rod 22 at its inner end is off-set as at 23 so as to form an abutment which is showing the be connected to the screw-threaded portion adapted to engage the shoulder 24 formed at the inner end of that portion of the bore of larger diameter.' The outer end of the electrode rod 22 is screwfthreade'd as at 24, and u on such screw-tlireaded portion is mounte a binding nut 25 which is adapted to abut against a cap iece 26 carried on the outer end of the ey indrical body 17. Mounted u on the screw-threaded portion 24 of the electrode rod 22 is a pair o wing nuts 27,28 under which is secured the leading-in-wire or circuit Wire connections, not shown.

Surrounding the outer portion of the cylindrical body 17 and abutting against the outer end of the section 14 is a dome-shaped shield 29 of a diameter reater than the diameter of the oil-set 5. elastic material so that the Wall of the`opening 3() which is provided in the shield will snu lly iit the cylindrical body 17. The sliie d 29 is so arranged as to enable the connecting up of the leading-in wires when occasion so requires without removing the shield, and furthermore the shield is so arranged that it is not necessary to remove it when it is desired to disconnect tlie plug from the engine cylinder. The position of the. shield is such as to prevent short-cir cuitin between the engine body and outer end o the plug if the plug should become Wet. Furthermore, the arrangement of the shield -is such that it leaves the outside terminal free of access and allows the operator to adjustI the various portions of the plug without removing the shield.

What'l claim is 1.` A spark plug comprising aninner and an outer section, said inner section terminating at its inner end ina pair of ixed lelectrodes, a body of insulating material secured within said sections by the outer of said sections, an electroderod extending through he shield 29 is formed of and for connecting a circuit wire therewith, a compression nut mounted upon the said inner section, and a water jacket formed integral with said inner section and independent of the Water jacket of the cylinder of the engine.

2. A spark plug comprising an inner and an outer section, said inner section termiiiating at its inner end in a pair of fixed electrodes, a body of insulating material secured within said sections by the outer of said sections, an electrode rod extending through said body and provided with an integral olfset abuttingagainst the body, said rod having its inner end extending between the iixed electrodes, a pluralit of nuts carried by the outerend of said rmi7 for fixing it in position and for connecting a circuit wire therewith, a compression nut mounted u A)on the said inner section, a water jacket 'ormed integral with said inner section and independent of the water jacket of the cylinder of the engine, and a dome-shaped shield snugly cngaging said body, arranged in close proximity to said outer section and extending towards said inner section.

3. A spark plug embodying a pair of terminals insulated from each other, a water jacket, and an elastic shield surroundin the insulation between the terminals, said s iield extending in close proximity to the water jacket.

4. A spark plug embodying a pair of terminals, an insulatin T medium between the terminals, and a shielil having an elastic portion contacting with the insulation, said elastic contacting portion adjusting itself to different diameters of insulators and watertight.

In testimony whereof l have hereunto set my hand in presence of' two subscribing witsaid body and provided with an integral oli'- g nesses.

set abutting against the body, said rod having its inner end extending between the fixed electrodes, a plurality of nuts carried by the outer end of said rod for fixing it in position WILLIAM B. HAYDEN.

Witnesses: l

GEORGE U. WHITE, RALPH B. CRUMMY. 

